Recent research has demonstrated that a child's gender has a significant impact on a wide range of family outcomes. Marriages with Sons tend to be more stable and traditional, exhibit greater father involvement, and generate greater satisfaction for both partners than marriages with daughters. The objective of the proposed work is to improve our understanding of parenthood and family processes by examining responses to child gender. To this end, we will: (1) conduct a comprehensive empirical study of the impact of child gender on a broad range of outcomes for U.S. families, (2) develop theoretical models of family behavior that incorporate child gender, and (3) generate testable hypotheses that distinguish among alternative models of the family and implement these tests. One focus of the work is the impact of child gender on the relationships between unmarried parents. Another is the effect of gender on fathers' family parenting and work behaviors. Since fathers' actions appear to be particularly sensitive to child gender, our results will help illuminate the nature of fathers' roles within the family. Our economic models incorporate differences in parental preferences towards, and differences in productivity in raising, boys and girls. Six data sets, including the PSID, NLSY79, Consumer Expenditure Survey, and the Fragile Families study, are used to address a set of specific research questions. These include: (1) the effect of child gender on the stability and quality of both marital and non-marital relationships and on the formation of new relationships; (2) the effect of gender on parental investments in marriage and family; (3) the relative well-being of mothers and fathers; and (4) the allocation of resources to children. Parental investments are reflected in expenditures on household public goods, measures of parental specialization, and indicators of dysfunctional behavior (such as parents' substance abuse). Detailed data on children's activities and environment capture various dimensions of parents' resource allocation.